This case is incredibly disturbing to me!
I genuinely cannot imagine the trauma of all of the people in her life or all of the people who were in or working at that store.
I can’t help but think it was a person in a management position- someone who had access to Gursimran, the cameras, oven, and how to operate the oven.
I don’t think there’s ANY way to pull the oven door shut once you’re in, correct?
I think in this case someone was very clever and put her in there after murdering her to obfuscate any evidence of foul play

Jmo!
But if it were someone else who put her in there, possibly after hurting or killing her, then that would mean that some person would have had to physically transport her to the bakery department and into the oven, all while the store was OPEN for business! With many customers and employees moving around everywhere all over the whole store at the same time!
Can't see how that would be possible.
Perhaps if the initial crime, if it happened, happened in the bakery department, so she at least wouldn't have had to be brought over from some other part of the store? Seems very unlikely IMO. But I could maybe see it if she and another person were both already in the bakery area, and someone shoved her into the oven, shut the door, and turned on oven, and then the person ran off. But all this while other employees must have been very nearby as well as customers right out front of the bakery who could have seen all this? And someone who doesn't belong in the employee part of the bakery would be easy to spot and report. Not to mention that I think the oven doors were supposedly openable from the inside?
But no other theory I can come up with makes any more sense, because nothing explains how she came to be inside, conscious or not, unable to exit, PLUS the oven being turned on at all. I assume the controls to turn the heat on in the oven are outside of the oven, right? Actually, I guess I don't know that, maybe they're on the inside, but I doubt it. But that's important; we need to know that. But how would it get turned on if they are on the outside, when no one had any reason to turn it on at all at that time (closing time on weekend)? Actually, it was way before closing time that she "disappeared", so we don't have any idea how long she was in there, neither with the oven on nor off. I mean she may have been in there for hours but the oven wasn't even on til much later. I don't know how long it would take for her to have the burns they said she did. Or she may have been somewhere else for those hours when no one knew where she was. But that would still mean someone would've had to get her over there and in the oven while store was open w/lots of people all over. Nope. And surely they know how long the oven was on for altogether. Wouldn't it have to be turned on hot with her inside for quite awhile for her to die in there? And I would imagine it's pretty obvious from the outside that the oven is on. I'd expect it to produce enough heat that people in the bakery department can tell it's on, and probably hear it too. And they said there was no reason for it to be on at all at that time, and bakery employees would know this. But does that mean they never use the oven for many hours before closing time on Saturday or whatever day it was? I guess that's possible.
Nothing so far explains this, imo.
Yet. Terrible, sad tragedy.